1. Field of the Invention
The present invention relates to the field of wide-angle illuminations, and more particularly to a light emitting diode (LED) lead frame and a lamp thereof capable of achieving a multi-directional illumination to increase the lateral illumination range.
2. Description of the Related Art
At present, most illumination lightbulbs adopt LED as an illumination light source to obtain uniform lights with a better color saturation. However, a conventional lightbulb is a point light source capable of achieving a 360-degree full directional light emission performance. On the other hand the LED is a plane light source with a limited range of diffusion angles, and thus it is a major issue for related manufacturers to improve the uniformity and illumination angle of the light source of a lightbulb.
Some countries set specifications (such as the Energy Star specification) for elements such as the light emitting angle and the brightness of the LED bulb to assure the light emitting performance. Therefore, the conventional LED bulb has to meet the minimum standard or requirement of the specification and tends to be designed with wide illumination angle and high light uniformity. A full directional LED lightbulb as disclosed in R.O.C. Pat. No. M460215 comprises a base, a circuit board, a light guide plate, at least one center LED, a plurality of peripheral LEDs and a lamp holder, wherein the light guide plate is installed on the circuit board, and each center LED installed on the circuit board is disposed in the light guide plate, and the lights are concentrated and projected to the front, and the peripheral LEDs disposed on the outer side of the light guide plate refracts light by a light reflective material on the outer side of the light guide plate to increase the light diffusion angle and the illumination angle.
The full directional LED lightbulb can improve the effect of the light diffusion angle and the illumination range by installing the LEDs at different positions (including the center LED and the peripheral LEDs together with the light guide plate). Since the volume of the LED is very small, therefore a lead frame is required in the manufacturing process and provided for connecting a conductive wire with an LED chip. However, the conventional LED lead frame has a light exit surface perpendicular to the surface of the circuit board, so that the center LED and the peripheral LEDs as disclosed in the foregoing patent emit light in a direction towards the lamp holder, and then the light guide plate is provided for changing the light diffusion path to achieve the aforementioned effect, and thus incurring a higher cost and consuming more assembling time, and the LEDs cannot produce the wide-angle light diffusion effect directly. Obviously, the light diffusion and illumination range of the conventional LED bulb have limitations and fail to obtain the best effect. Therefore, the inventor of the present invention based on years of experience in the related industry to conduct extensive researches and experiments, and finally developed an LED lead frame and a lamp thereof, in hope of overcoming the drawbacks of the conventional LED bulb.